[llvm-branch-commits] [llvm] [LV] Mask off possibly aliasing vector lanes (PR #100579)

[Sam Tebbs via llvm-branch-commits]

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@@ -974,6 +974,11 @@ AArch64TTIImpl::getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,
     }
     break;
   }
+  case Intrinsic::loop_dependence_raw_mask:
+  case Intrinsic::loop_dependence_war_mask:
+    if (ST->hasSVE2())
+      return 1;
+    return InstructionCost::getInvalid(CostKind);
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SamTebbs33 wrote:

The intrinsics do expand into a [lot of instructions](https://github.com/llvm/llvm-project/pull/117007/files#diff-d7065626b3d269e24241429ce037d51fc91d5ead5896d67fcc038aefc1111fd2R1806), so I'm keen to hear people's opinions on whether invalid is better than calculating the cost of them, since that will probably be very high.

https://github.com/llvm/llvm-project/pull/100579